.list {
  position: relative;
  background-color: #ccc;
  width: 300px;
}

.list-item {
  height: 40px;
  line-height: 40px;
  border-bottom: 1px solid #666;
  background-color: #fff;
}

.cover-mask {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
}
